Editable (non-readonly) combobox

[b0g2]

Currently, the commandline combobox is read-only (there is no textbox). As an enhancement, I would like to be able to type text directly into the combobox. When regularly changing the command line, this would avoid switching to the project settings page over and over again. Especially when picking an existing item from the combobox and making a small modification (like reusing some debug command line switches but entering a new filename). This would be particularly useful when developing applications that support a lot of command line options.